In conventional displays based on CRTs (Cathode Ray Tubes), liquid crystal panels, or projectors, an image captured, for example, by a video camera (hereinafter simply referred to as a camera when appropriate) is displayed, which is simply as viewed from a camera's position as a viewpoint, as shown in FIG. 1.
Thus, for example, even when a user moves his/her head to change his/her viewpoint for viewing an image displayed on a display, the image displayed on the display remains an image as viewed from a lens center of the camera (hereinafter referred to as a camera's viewpoint when appropriate), and the image displayed on the display does not change in accordance with the change in the user's viewpoint.
In view of this situation, as an example of image display method by which an image displayed on a display changes in accordance with a user's viewpoint, a method called zebra imaging is used.
However, zebra imaging is a method based on holography. Since an image displayed by zebra imaging is a hologram, a large amount of computation and time is required for generating the image.
As another example of image display method by which an image displayed on a display changes in accordance with a user's viewpoint, VR (Virtual Reality) systems based on IPT (Immersive Projection Technology) or IPD (Immersive Projection Display), such as CAVE developed at Illinois University, are known.
However, such VR systems are directed to images of CG (Computer Graphics), and it is difficult to display real images captured by video cameras.